Organic light emitting display apparatus and method of manufacturing the same

ABSTRACT

An organic light emitting display apparatus and a method of manufacturing the same are disclosed. The organic light emitting display apparatus includes, for example, a bus electrode, an insulating layer covering the bus electrode and having a bus electrode hole exposing at least a part of the bus electrode, a pixel electrode formed on the insulating layer and electrically coupled with the bus electrode, a pixel defining layer exposing a part of the pixel electrode and a part of the bus electrode, a first intermediate layer on the pixel defining layer and the pixel electrode, the first intermediate layer having a first opening to expose the part of the bus electrode, an emission layer disposed on the first intermediate layer, and an opposite electrode to correspond to the pixel electrode and the bus electrode and contacting the bus electrode through the first opening and the bus electrode hole.

INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS

Any and all applications for which a foreign or domestic priority claimis identified in the Application Data Sheet as filed with the presentapplication are hereby incorporated by reference under 37 CFR 1.57. Forexample, this application is a continuation-in-part of U.S. applicationSer. No. 14/012,725, filed on Aug. 28, 2013, which claims the benefit ofKorean Patent Application No. 10-2013-0063082, filed on May 31, 2013, inthe Korean Intellectual Property Office, the disclosure of each of whichis incorporated herein in its entirety by reference. Further, thisapplication claims the benefit of Korean Patent Application No.10-2014-0066528, filed on May 30, 2014, the disclosure of which isincorporated herein in its entirety by reference.

BACKGROUND

1. Field

The present disclosure relates to an organic light emitting displayapparatus and a method of manufacturing the same, and more particularly,to an organic light emitting display apparatus that may be easilymanufactured and has high brightness stability, and a method ofmanufacturing the same.

2. Description of the Related Technology

Organic light emitting displays have a plurality of pixels, each pixelincluding an organic light emitting device. The organic light emittingdevice has a pixel electrode, an opposite electrode facing the pixelelectrode, and an intermediate layer interposed between the pixelelectrode and the opposite electrode and including an emission layer(EML). The pixel electrode is patterned in each pixel in an islandshape, and the opposite electrode is formed integral to the plurality ofpixels. However, in some organic light emitting display apparatuses, anIR drop occurs in the opposite electrode and an unintended brightnessdifference occurs in the plurality of pixels.

SUMMARY OF CERTAIN INVENTIVE ASPECTS

In one aspect, an organic light emitting display apparatus is providedthat may be easily manufactured and has high luminous stability.

In another aspect, a method of manufacturing an organic light emittingdisplay apparatus is provided.

In another aspect, an organic light emitting display apparatus isprovided, including, for example, a bus electrode, an insulating layercovering the bus electrode and having a bus electrode hole so that atleast a part of the bus electrode is exposed through the bus electrodehole, a pixel electrode formed on the insulating layer and electricallycoupled with the bus electrode, a pixel defining layer formed on theinsulating layer so that at least a part of the pixel electrodeincluding a central part thereof and at least the part of the buselectrode exposed through the bus electrode hole are exposed, a firstintermediate layer formed on the pixel defining layer and the pixelelectrode, the first intermediate having a first opening correspondingto the bus electrode hole of the insulating layer so that at least thepart of the bus electrode is exposed, an emission layer formed on thefirst intermediate layer to correspond to the pixel electrode, and anopposite electrode formed on the emission layer to correspond to thepixel electrode and the bus electrode, the opposite electrode contactingthe bus electrode through the first opening of the first intermediatelayer and the bus electrode hole of the insulating layer.

In some embodiments, the organic light emitting display apparatus mayfurther comprise a thin film transistor including a source electrode, adrain electrode, and the gate electrode, wherein the bus electrode is ona same layer as at least one of the source electrode, drain electrode,and the gate electrode. In some embodiments, the source electrode andthe drain electrode are located above the gate electrode, and the buselectrode is on a same layer as the source electrode and the drainelectrode. In some embodiments, the first opening of the firstintermediate layer exposes only a part of the bus electrode. In someembodiments, a portion of the first intermediate layer adjacent to thefirst opening may be a portion deteriorated through exposure tohigh-temperature heat. In some embodiments, the organic light emittingdisplay apparatus may further include an auxiliary opposite electrodeformed on a surface toward the first intermediate layer of the oppositeelectrode to contact the opposite electrode, the auxiliary oppositeelectrode having a third opening corresponding to the first opening ofthe first intermediate layer. In some embodiments, a thickness of theauxiliary opposite electrode may be smaller than the thickness of theopposite electrode. In some embodiments, the auxiliary oppositeelectrode may correspond to the opposite electrode in a portion of thefirst intermediate layer not including the first opening. In someembodiments, a thickness of a portion of the opposite electrodecorresponding to the first opening of the first intermediate layer maybe smaller than the thickness of another portion of the oppositeelectrode.

In some embodiments, the organic light emitting display apparatus mayfurther include a second intermediate layer formed between the firstintermediate layer and the opposite electrode to cover the firstintermediate layer and the emission layer. In some embodiments, thesecond intermediate layer has a second opening corresponding to thefirst opening of the first intermediate layer so that the oppositeelectrode contacts the bus electrode through the first opening and thesecond opening. In some embodiments, the second opening may be largerthan the first opening. In some embodiments, a center of the secondopening and a center of the first opening are substantially aligned witheach other when viewed in a direction substantially normal to the firstand the second opening. In some embodiments, a portion of the secondintermediate layer adjacent to the second opening may be a portion thatis deteriorated by exposure to heat. In some embodiments, the secondintermediate layer may include at least one of LiF and Liq.

In another aspect, a method of manufacturing an organic light emittingdisplay apparatus is provided that includes, for example, forming a buselectrode, forming an insulating layer covering the bus electrode,forming a pixel electrode on the insulating layer, forming a pixeldefining layer on the insulating layer so that at least a part of thepixel electrode including a central part thereof is exposed, forming afirst intermediate layer on the pixel defining layer and the pixelelectrode, forming an emission layer on the first intermediate layer tocorrespond to the pixel electrode, exposing at least a part of the buselectrode, and forming an opposite electrode corresponding to the pixelelectrode and the bus electrode to contact the bus electrode.

In some embodiments, the forming of the bus electrode comprises formingthe bus electrode on a same layer as at least one of a source electrode,a drain electrode, and a gate electrode of a thin film transistor. Insome embodiments, the method may further comprise forming a buselectrode hole exposing at least the part of the bus electrode byremoving at least a portion of the insulating layer corresponding to thebus electrode, wherein the forming of the pixel defining layer comprisesforming the pixel defining layer on the insulating layer so that atleast the part of the bus electrode exposed through the bus electrodehole is exposed, wherein the forming of the first intermediate layercomprises forming the first intermediate layer on the pixel defininglayer, the pixel electrode, and the bus electrode, and wherein theexposing at least the part of the bus electrode comprises forming afirst opening by removing a portion of the first intermediate layer onthe bus electrode. In some embodiments, the forming of the first openingmay include forming the first opening through which only a part of thebus electrode is exposed.

In some embodiments, the forming of the first opening may be achieved byirradiating a laser beam onto the first intermediate layer. In someembodiments, the method may further include, between the forming of theemission layer and the forming of the first opening: forming anauxiliary opposite electrode corresponding to the pixel electrode andthe bus electrode. In some embodiments, the first opening in the firstintermediate layer is formed along with a third opening in the auxiliaryopposite electrode by removing a portion of the first intermediate layeron the bus electrode and a portion of the auxiliary opposite electrodeon the bus electrode so that at least a part of the bus electrode isexposed. In some embodiments, the opposite electrode is formed tocorrespond to the pixel electrode and the bus electrode to contact thebus electrode through the first opening in the first intermediate layerand the third opening in the auxiliary opposite electrode. In someembodiments, the first opening in the first intermediate layer and thethird opening in the auxiliary opposite electrode may be simultaneouslyformed by irradiating a laser beam onto the auxiliary oppositeelectrode. In some embodiments, the opposite electrode may be formed tobe thicker than the auxiliary opposite electrode.

In some embodiments, the method may further include, between the formingof the emission layer and the forming of the first opening, forming asecond intermediate layer to cover the first intermediate layer and theemission layer. In some embodiments, the first opening in the firstintermediate layer is formed along with a second opening in the secondintermediate layer by removing a portion of the first intermediate layeron the bus electrode and a portion of the second intermediate layer onthe bus electrode so that at least a part of the bus electrode is ableto be exposed; and the opposite electrode is formed to correspond to thepixel electrode and the bus electrode to contact the bus electrodethrough the first opening of the first intermediate layer and the secondopening of the second intermediate layer. In some embodiments, the firstopening in the first intermediate layer and the second opening in thesecond intermediate layer may be simultaneously formed by irradiating alaser beam onto the second intermediate layer.

In some embodiments, the forming of the pixel defining layer comprisesforming the pixel defining layer on the insulating layer so that atleast the part of the pixel electrode including the central part thereofand at least a part of the insulating layer corresponding to the buselectrode are exposed, and wherein the exposing at least the part of thebus electrode comprises forming a bus electrode hole of the insulatinglayer and a first opening of the first intermediate layer by removing aportion of the insulating layer on the bus electrode and a portion ofthe first intermediate layer on the bus electrode so that at least thepart of the bus electrode is exposed. In some embodiments, the formingof the bus electrode hole and the first opening comprises irradiating alaser beam onto the first intermediate layer. In some embodiments, themethod may further comprise after the forming of the emission layer andbefore the forming of the bus electrode hole and the first opening,forming an auxiliary opposite electrode corresponding to the pixelelectrode and the bus electrode, wherein the forming of the buselectrode hole and the first opening comprises forming a bus electrodehole of the insulating layer, a first opening of the first intermediatelayer, and a third opening of the auxiliary opposite electrode byremoving a portion of the insulating layer on the bus electrode, aportion of the first intermediate layer on the bus electrode, and aportion of the auxiliary opposite electrode on the bus electrode so thatat least the part of the bus electrode is exposed, and wherein theforming of the opposite electrode comprises forming the oppositeelectrode to correspond to the pixel electrode and the bus electrode tocontact the bus electrode through the bus electrode hole in theinsulating layer, the first opening in the first intermediate layer, andthe third opening in the auxiliary opposite electrode. In someembodiments, the forming of the bus electrode hole, the first opening,and the third opening comprises irradiating a laser beam onto theauxiliary opposite electrode so that the bus electrode hole, the firstopening, and the third opening are simultaneously formed. In someembodiments, the opposite electrode is formed to be thicker than theauxiliary opposite electrode.

In some embodiments, the method may further comprise, after the formingof the emission layer and before the forming of the first opening,forming a second intermediate layer to cover the first intermediatelayer and the emission layer, wherein the forming of the bus electrodehole and the first opening comprises forming a bus electrode hole of theinsulating layer, a first opening of the first intermediate layer, and asecond opening of the second intermediate layer by removing a portion ofthe insulating layer on the bus electrode, a portion of the firstintermediate layer on the bus electrode, and a portion of the secondintermediate layer on the bus electrode so that at least the part of thebus electrode is exposed, and wherein the forming of the oppositeelectrode comprises forming the opposite electrode to correspond to thepixel electrode and the bus electrode to contact the bus electrodethrough the bus electrode hole in the insulating layer, the firstopening in the first intermediate layer, and the second opening in thesecond intermediate layer. In some embodiments, wherein the forming ofthe bus electrode hole, the first opening, and the second openingcomprises irradiating a laser beam onto the second intermediate layer sothat the bus electrode hole, the first opening, and the second openingare simultaneously formed.

In another aspect, a method of manufacturing an organic light emittingdisplay apparatus is provided that includes, for example, forming a buselectrode, forming an insulating layer covering the bus electrode,forming a pixel electrode on the insulating layer, forming a pixeldefining layer on the insulating layer so that at least a part of thepixel electrode including a central part thereof is exposed, forming afirst intermediate layer on the pixel defining layer and the pixelelectrode, forming an emission layer on the first intermediate layer tocorrespond to the pixel electrode, forming an opposite electrodecorresponding to the pixel electrode and the bus electrode, andirradiating a laser beam onto at least a part of the opposite electrodecorresponding to the bus electrode so that at least a part of layersbetween the opposite electrode and the bus electrode is removed and theopposite electrode and the bus electrode contact each other.

BRIEF DESCRIPTION OF THE DRAWINGS

Features of the present disclosure will become more fully apparent fromthe following description and appended claims, taken in conjunction withthe accompanying drawings. It will be understood these drawings depictonly certain embodiments in accordance with the disclosure and,therefore, are not to be considered limiting of its scope; thedisclosure will be described with additional specificity and detailthrough use of the accompanying drawings. An apparatus, system or methodaccording to some of the described embodiments can have several aspects,no single one of which necessarily is solely responsible for thedesirable attributes of the apparatus, system or method. Afterconsidering this discussion, and particularly after reading the sectionentitled “Detailed Description of Certain Inventive Embodiments” onewill understand how illustrated features serve to explain certainprinciples of the present disclosure.

FIGS. 1 through 7 are cross-sectional views schematically illustratingprocesses of a method of manufacturing an organic light emitting displayapparatus.

FIG. 8 is a photo schematically showing a part of the organic lightemitting display apparatus illustrated in FIG. 6.

FIGS. 9 through 12 are cross-sectional views schematically illustratingprocesses of a method of manufacturing an organic light emitting displayapparatus.

FIG. 13 is a cross-sectional view schematically illustrating an organiclight emitting display apparatus that is manufactured by a method ofmanufacturing an organic light emitting display apparatus.

FIG. 14 is a cross-sectional view schematically illustrating one processof the method of manufacturing an organic light emitting displayapparatus illustrated in FIG. 13.

FIGS. 15 through 18 are cross-sectional views schematically illustratingprocesses of a method of manufacturing an organic light emitting displayapparatus.

FIGS. 19 through 21 are cross-sectional views schematically illustratingprocesses of a method of manufacturing an organic light emitting displayapparatus.

FIG. 22 is a cross-sectional view schematically illustrating an organiclight emitting display apparatus that is manufactured by a method ofmanufacturing an organic light emitting display apparatus.

FIGS. 23 through 26 are cross-sectional views schematically illustratingprocesses of a method of manufacturing an organic light emitting displayapparatus.

FIGS. 27 through 29 are cross-sectional views schematically illustratingprocesses of a method of manufacturing an organic light emitting displayapparatus.

FIG. 30 is a cross-sectional view schematically illustrating an organiclight emitting display apparatus that is manufactured by a method ofmanufacturing an organic light emitting display apparatus.

FIG. 31 is cross-sectional view schematically illustrating process of amethod of manufacturing an organic light emitting display apparatus.

FIG. 32 is cross-sectional view schematically illustrating process of amethod of manufacturing an organic light emitting display apparatus.

DETAILED DESCRIPTION OF CERTAIN INVENTIVE EMBODIMENTS

Reference will now be made in detail to exemplary embodiments, examplesof which are illustrated in the accompanying drawings. However,exemplary embodiments are not limited to the embodiments illustratedhereinafter, and the embodiments herein are rather introduced to provideeasy and complete understanding of the scope and spirit of exemplaryembodiments. In the drawings, elements may be exaggerated or reduced forconveniences of explanation. For example, the sizes and the thicknessesof elements are arbitrarily shown for convenience of explanation andthus, the present disclosure is not limited thereto. It will beunderstood that when an element, such as a layer, a region, or asubstrate, is referred to as being “on”, “connected to” or “coupled to”another element, it may be directly on, connected or coupled to theother element, or intervening elements may be present. As used herein,the term “and/or” includes any and all combinations of one or more ofthe associated listed items. Expressions such as “at least one of,” whenpreceding a list of elements, modify the entire list of elements and donot modify the individual elements of the list.

FIGS. 1 through 7 are cross-sectional views schematically illustratingprocesses of a method of manufacturing an organic light emitting displayapparatus, according to embodiments of the present disclosure.

First, in some embodiments as illustrated in FIG. 1, a pixel electrode210 and a bus electrode 210 a are formed on the same layer. The pixelelectrode 210 and the bus electrode 210 a are spaced apart andelectrically insulated from each other. In FIG. 1, the pixel electrode210 and the bus electrode 210 a are formed on a planarization layer 170.However, aspects of the present disclosure are not limited thereto.

Prior to forming the pixel electrode 210 and the bus electrode 210 a,various layers may be formed. In the drawings, a thin film transistorTFT and a capacitor Cap are formed on a substrate 100, the planarizationlayer 170 is formed to cover the thin film transistor TFT and thecapacitor Cap, and then, the pixel electrode 210 and the bus electrode210 a are formed on the planarization layer 170.

The substrate 100 may be formed from one of various materials includinga glass material, a metal material, and a plastic material, such aspolyethylene terephthalate (PET), polyethylene naphthalate (PEN), orpolyimide. A buffer layer 110 formed on the substrate 100 to preventimpurities from permeating a semiconductor layer of the thin filmtransistor TFT, a gate insulating layer 130 is formed on the bufferlayer 110 to insulate the semiconductor layer and the gate electrode ofthe thin film transistor TFT from each other, an interlayer dielectric(ILD) layer 150 is formed on the gate insulating layer 130 to insulate asource electrode/drain electrode and the gate electrode of the thin filmtransistor TFT from each other, and the planarization layer 170 isformed on the interlayer dielectric (ILD) layer 150 to cover the thinfilm transistor TFT. The planarization layer 170 has an approximatelyflat top surface. Other elements may be formed on the buffer layer 110.

The pixel electrode 210 and the bus electrode 210 a may be (semi-)transparent electrodes or reflection electrodes. When the pixelelectrode 210 and the bus electrode 210 a are (semi-)transparentelectrodes, the pixel electrode 210 and the bus electrode 210 a may beformed from, for example, an indium tin oxide (ITO), an indium zincoxide (IZO), a zinc oxide (ZnO), an indium oxide (In₂O₃), an indiumgallium oxide (IGO), or an aluminum zinc oxide (AZO). When the pixelelectrode 210 and the bus electrode 210 a are reflection electrodes, areflection layer may be formed from Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir,Cr, or a combination thereof, and a layer formed from ITO, IZO, ZnO orIn₂O₃ may be formed on the reflection layer. The pixel electrode 210 andthe bus electrode 210 a may be simultaneously formed from the samematerial.

Subsequently, a pixel defining layer 180 is formed on the same layer asthe pixel electrode 210 and the bus electrode 210 a so that at least apart of the pixel electrode 210 including a central part thereof and atleast a part of the bus electrode 210 a may be exposed. The pixeldefining layer 180 has an opening corresponding to each subpixel, forexample, an opening through which at least a part of the pixel electrode210 including the central part thereof is exposed, thereby definingpixels. The pixel defining layer 180 causes a distance between an end ofthe pixel electrode 210 and an opposite electrode (not shown) at anupper portion of the pixel electrode 210 that will be formed later toincrease, thereby preventing an arc from occurring at the end of thepixel electrode 210.

Subsequently, in some embodiments as illustrated in FIG. 2, a firstintermediate layer 221 is formed on a top surface of the pixel defininglayer 180 between the pixel electrode 210 and the bus electrode 210 a,the pixel electrode 210, and the bus electrode 210 a. That is, the firstintermediate layer 221 may be formed so that the top surface of thepixel defining layer 180 between the pixel electrode 210 and the buselectrode 210 a, the pixel electrode 210, and the bus electrode 210 amay be formed integrally with one another in a plurality of pixels.

In some embodiments, the first intermediate layer 221 may have a singlelayer structure or a multi-layered structure. For example, when thefirst intermediate layer 221 is formed from a polymer material, thefirst intermediate layer 221 is a hole transport layer (HTL) having asingle layer structure and may be formed frompoly-(3,4)-ethylene-dihydroxy thiophene (PEDOT) or polyaniline (PANI).When the first intermediate layer 221 is formed from a low molecularmaterial, the first intermediate layer 221 may include a hole injectionlayer (HIL) and a HTL.

Subsequently, as illustrated in FIG. 3, an emission layer (EML) 223 isformed on the first intermediate layer 221 to correspond to the pixelelectrode 210.

Subsequently, in some embodiments as illustrated in FIG. 4, a secondintermediate layer 222 is formed to cover the first intermediate layer221 and the emission layer (EML) 223. Obviously, the second intermediatelayer 222 is not necessarily formed, and for example, when the firstintermediate layer 221 and the EML 223 are formed from a polymermaterial, the second intermediate layer 222 may not be formed. When thefirst intermediate layer 221 and the EML 223 are formed from a lowmolecular material, the second intermediate layer 222 may be formed sothat an organic light emitting device has superior characteristics. Insome embodiments, the second intermediate layer 222 may have a singlelayer structure or a multi-layered structure. The second intermediatelayer 222 may include an electron transport layer (ETL) and/or anelectron injection layer (EIL).

In some embodiments, after the second intermediate layer 222 is formedas illustrated in FIG. 6, a part of the first intermediate layer 221 onthe bus electrode 210 a and a part of the second intermediate layer 222on the bus electrode 210 a are removed so that a first opening 221′ ofthe first intermediate layer 221 and a second opening 222′ of the secondintermediate layer 222 may be formed. As a result, at least a part ofthe bus electrode 210 a may be exposed. To this end, as illustrated inFIG. 5, a laser beam is irradiated onto the second intermediate layer222 so that the first opening 221′ of the first intermediate layer 221and the second opening 222′ of the second intermediate layer 222 may besimultaneously formed.

Subsequently, in some embodiments as illustrated in FIG. 7, an oppositeelectrode 230 corresponding to the pixel electrode 210 and the buselectrode 210 a is formed to contact the bus electrode 210 a through thefirst opening 221′ of the first intermediate layer 221 and the secondopening 222′ of the second intermediate layer 222. The oppositeelectrode 230 may be formed as an integral part in a plurality of pixelsand may cover a display region (active region). The display region meansall regions of the entire organic light emitting display apparatus inwhich light may be emitted, for example, all regions excluding edges ofthe organic light emitting display apparatus in which a controller is tobe disposed. Obviously, when a dead area does not exist in the entiresurface of the organic light emitting display apparatus, the entiresurface of the organic light emitting display apparatus may be thedisplay region.

The opposite electrode 230 may contact electrode power supply linesoutside the display region and may receive electrical signals from theelectrode power supply lines. The opposite electrode 230 may be a(semi-)transparent electrode or a reflection electrode. When theopposite electrode 230 is a (semi-)transparent electrode, a layer may beformed from Li, Ca, LiF/Ca, LiF/Al, Al, Mg, or a combination thereof, alayer may be formed from a (semi-)transparent material, such as ITO,IZO, ZnO, or In₂O₃ on the layer so that the opposite electrode 230 maybe formed as the (semi-)transparent electrode. When the oppositeelectrode 230 is a reflection electrode, a layer may be formed from atleast one from among Li, Ca, LiF/Ca, LiF/Al, Al, Ag, and Mg so that theopposite electrode 230 may be formed as the reflection electrode.Obviously, the configuration and material of the opposite electrode 230are not limited thereto, and various modifications like forming theopposite electrode 230 of other materials or forming the oppositeelectrode 230 to have a multi-layered structure are possible.

In the method of manufacturing the organic light emitting displayapparatus according to the current embodiment of the present disclosure,after the bus electrode 210 a is formed, the opposite electrode 130contacts the bus electrode 210 a, and electrical signals are transmittedto the opposite electrode 230 via the bus electrode 210 a having highelectrical conductivity. Thus, an IR drop that may occur in the oppositeelectrode 230 when no bus electrode 210 a is present may be prevented orminimized. Thus, an unintended brightness difference may be preventedfrom being generated in the plurality of pixels, or even when theunintended brightness difference is generated, the brightness differencemay be minimized.

To allow the opposite electrode 230 and the bus electrode 210 a tocontact each other, as illustrated in FIG. 7, at least a part of the buselectrode 210 a need not be covered by the first intermediate layer 221and the second intermediate layer 222. To this end, from a time when thefirst intermediate layer 221 and the second intermediate layer 222 areinitially formed, the first intermediate layer 221 and the secondintermediate layer 222 may not be formed on at least a part of the buselectrode 210 a. However, in this case, a mask must be used to form thefirst intermediate layer 221 and the second intermediate layer 222.Thus, a manufacturing process may be complicated when the mask and thesubstrate 100 need to be precisely aligned.

However, in the method of manufacturing the organic light emittingdisplay apparatus according to the current embodiment of the presentdisclosure, the first intermediate layer 221 and the second intermediatelayer 222 are formed on the entire surface of the substrate 100, andonly portions of the first intermediate layer 221 and the secondintermediate layer 222 on at least a part of the bus electrode 210 a areselectively removed using the laser beam so that manufacturingefficiency may be remarkably improved.

FIG. 8 is a photo schematically showing a part of the organic lightemitting display apparatus illustrated in FIG. 6. In some embodiments asillustrated in FIG. 8, as the laser beam is irradiated onto the secondintermediate layer 222, portions of the first intermediate layer 221 andthe second intermediate layer 222 are removed so that a part of the buselectrode 210 a may be exposed. As the laser beam is directly irradiatedonto the second intermediate layer 222, as illustrated in FIG. 8, thesecond opening 222′ of the second intermediate layer 222 onto which thelaser beam is directly irradiated may be larger than the first opening221′ of the first intermediate layer 221. In FIG. 8, the first opening221′ and the second opening 222′ have approximately circular shapes, anda radius r2 of the second opening 222′ may be larger than a radius r1 ofthe first opening 221′.

As described above, if the second intermediate layer 222 is not formed,the laser beam is directly irradiated onto the first intermediate layer221, a part of the first intermediate layer 221 on the bus electrode 210a is removed so that at least a part of the bus electrode 210 a may beexposed, thereby forming the first opening 221′. When the oppositeelectrode 230 is formed, the opposite electrode 230 corresponding to thepixel electrode 210 and the bus electrode 210 a is formed to contact thebus electrode 210 a via the first opening 221′ of the first intermediatelayer 221.

When the first opening 221′ and/or the second opening 222′ is formed, asillustrated in FIG. 8, only a part of the bus electrode 210 a may beexposed. For example, a plurality of first openings 221′ and/or secondopenings 222′ having approximately circular shapes as illustrated inFIG. 8 are formed in the display region of the organic light emittingdisplay region so that the opposite electrode 230 may contact aplurality of the bus electrodes 210 a.

FIGS. 9 through 12 are cross-sectional views schematically illustratingprocesses of a method of manufacturing an organic light emitting displayapparatus, according to other embodiments of the present disclosure.

In the method of manufacturing the organic light emitting displayapparatus according to the current embodiment of the present disclosure,as described above with reference to FIGS. 1 through 4, the secondintermediate layer 222 is formed, and in some embodiments as illustratedin FIG. 9, an auxiliary opposite electrode 231 corresponding to thepixel electrode 210 and the bus electrode 210 a is formed. That is, theauxiliary opposite electrode 231 is formed to cover the secondintermediate layer 222. If the second intermediate layer 222 is notformed, the auxiliary opposite electrode 231 may be formed to cover thefirst intermediate layer 221 and the EML 223. A material for forming theauxiliary opposite electrode 231 may be one of the above-describedmaterials used for forming the opposite electrode 230, for example.

Subsequently, in some embodiments as illustrated in FIG. 10, the laserbeam is irradiated onto the auxiliary opposite electrode 231, and thefirst opening 221′ of the first intermediate layer 221, the secondopening 222′ of the second intermediate layer 222, and a third opening231′ of the auxiliary opposite electrode 231 are simultaneously formed,in some embodiments as illustrated in FIG. 11. Obviously, if the secondintermediate layer 222 is not formed, the laser beam is irradiated ontothe auxiliary opposite electrode 231 so that the first opening 221′ ofthe first intermediate layer 221 and the third opening 231′ of theauxiliary opposite electrode 231 may be simultaneously formed.

Subsequently, in some embodiments as illustrated in FIG. 12, theopposite electrode 230 corresponding to the pixel electrode 210 and thebus electrode 210 a is formed to contact the bus electrode 210 a throughthe first opening 221′ of the first intermediate layer 221, the secondopening 222′ of the second intermediate layer 222, and the third opening231′ of the auxiliary opposite electrode 231. Even in this case, theopposite electrode 230 may be formed as an integral part in theplurality of pixels and may cover the display region (active region).

In the method of manufacturing the organic light emitting displayapparatus according to the present embodiment, the bus electrode 210 ais formed, and the opposite electrode 230 contacts the bus electrode 210a, and electrical signals are transmitted to the opposite electrode 230via the bus electrode 210 a having high electrical conductivity. Thus,an IR drop that may occur when no bus electrode 210 a is present may beprevented or minimized. Thus, an unintended brightness difference may beprevented from being generated in the plurality of pixels, or even whenthe unintended brightness difference is generated, the brightnessdifference may be minimized.

The first intermediate layer 221 and/or the second intermediate layer222 is formed on the entire surface of the substrate 100, and onlyportions of the first intermediate layer 221 and the second intermediatelayer 222 on at least a part of the bus electrode 210 a are selectivelyremoved using the laser beam to allow the opposite electrode 230 and thebus electrode 210 a to contact each other. Thus, manufacturingefficiency may be significantly improved when compared similar processesknown in the art.

In the method of manufacturing the organic light emitting displayapparatus according to the present embodiment, if the secondintermediate layer 222 is not formed using the auxiliary oppositeelectrode 231, the first intermediate layer 221 and the EML 223 arecovered and then the laser beam is irradiated onto the auxiliaryopposite electrode 231. The laser beam is irradiated onto the auxiliaryopposite electrode 231 in a state in which the first intermediate layer221 that is vulnerable to an impurity from the outside, the secondintermediate layer 222 and/or the EML 223 are covered with the auxiliaryopposite electrode 231. Thus, compared to the case when the laser beamis irradiated onto the first intermediate layer 221 and/or the secondintermediate layer 222 without covering the auxiliary opposite electrode231, damage of the first intermediate layer 221, the second intermediatelayer 222 and/or the EML 223 may be minimized, and the occurrence of amanufacturing defect may be remarkably reduced.

In the method of manufacturing the organic light emitting displayapparatus, the laser beam is irradiated onto the auxiliary oppositeelectrode 231, thereby removing a part of the auxiliary oppositeelectrode 231. Thus, the auxiliary opposite electrode 231 may be formedwith a small thickness so that the part of the auxiliary oppositeelectrode 231 may be easily removed. If light generated in the EML 223is irradiated to the outside through the substrate 100, the oppositeelectrode 230 may be formed with a sufficient large thickness inconsideration of electrical conductivity. As a result, the oppositeelectrode 230 may be formed thicker than the auxiliary oppositeelectrode 231.

When the auxiliary opposite electrode 231 and the opposite electrode 230are formed from the same material, a boundary between the auxiliaryopposite electrode 231 and the opposite electrode 230 may not occur in afinal product according to a process condition. In some embodiments, theauxiliary opposite electrode 231 and the opposite electrode 230 may bereferred to the opposite electrode 230. As illustrated in FIG. 13, athickness t1 of another portion of the opposite electrode 230, forexample, the thickness t1 of a portion of the pixel electrode 210 islarger than the thickness t2 of a portion of the opposite electrode 230where the opposite electrode 230 contacts the bus electrode 210 a. Thisis because, in the portion of the pixel electrode 210, the oppositeelectrode 230 is formed twice and in the portion of the bus electrode210 a, the opposite electrode 230 is formed once.

FIG. 14 is a cross-sectional view schematically illustrating one processof the method of manufacturing an organic light emitting displayapparatus illustrated in FIG. 13. In the method of manufacturing theorganic light emitting display apparatus illustrated in FIG. 13, thefirst intermediate layer 221, the EML 223 and/or the second intermediatelayer 222 are formed as illustrated in FIG. 5, and the oppositeelectrode 230 is formed on the entire surface of the display unit asillustrated in FIG. 14. Next, a laser beam is irradiated onto at least apart of the opposite electrode 230 corresponding to the bus electrode210 a so that at least a part of the first intermediate layer 221 and/orthe second intermediate layer 222 between the opposite electrode 230 andthe bus electrode 210 a is removed and the opposite electrode 230 andthe bus electrode 210 a contact each other. At least a part of the firstintermediate layer 221 and/or the second intermediate layer 222 betweenthe opposite electrode 230 and the bus electrode 210 a is removed togenerate heat in the opposite electrode 230 by the laser beam irradiatedonto the opposite electrode 230 and to remove the first intermediatelayer 221 and/or the second intermediate layer 222 between the oppositeelectrode 230 and the bus electrode 210 a due to heat.

Until now, the bus electrode 210 a that is disposed on the same layer asthe pixel electrode 210 has been described. However, aspects of thepresent disclosure are not limited thereto. For example, the buselectrode 210 a may also be disposed on the same layer as one electrodeof the thin film transistor TFT. Hereinafter, the latter case will bedescribed.

FIGS. 15 through 18 are cross-sectional views schematically illustratingprocesses of a method of manufacturing an organic light emitting displayapparatus.

First, as illustrated in FIG. 15, a bus electrode AL is formed on asubstrate 100, and a planarization layer 170 is formed as an insulatinglayer that covers the bus electrode AL, and a pixel electrode 210 isformed on the planarization layer 170, and then, a pixel defining layer180 is formed on the planarization layer 170 so that at least a part ofthe pixel electrode 210 including a central part thereof may be exposed.In this case, the pixel defining layer 180 may be formed on theplanarization layer 170 so that at least a part of the planarizationlayer 170 corresponding to the bus electrode AL may be exposed. Theplanarization layer 170 is illustrated in FIG. 15. However, theplanarization layer 17 may be replaced with an insulating layer, such asa planarized or unplanarized protection layer. This also applies to thefollowing embodiments and modifications thereof.

When the bus electrode AL is formed, the bus electrode AL may be formedon the same layer as at least one of a source electrode, a drainelectrode, and a gate electrode of the thin film transistor TFT. In FIG.15, the bus electrode AL is formed on the same layer as the sourceelectrode and the drain electrode of the thin film transistor TFT, i.e.,on an interlayer dielectric (ILD) layer 150. Obviously, the buselectrode AL may be simultaneously formed from the same material as thesource electrode and the drain electrode of the thin film transistorTFT.

Subsequently, as illustrated in FIG. 16, a first intermediate layer 221is formed on the pixel defining layer 180 and the pixel electrode 210,and an emission layer (EML) 223 is formed on the first intermediatelayer 221 to correspond to the pixel electrode 210. The firstintermediate layer 221 may be formed as an integral part in a pluralityof pixels. The first intermediate layer 221 may have a single layerstructure or a multi-layered structure. For example, when the firstintermediate layer 221 is formed from a polymer material, the firstintermediate layer 221 may be a hole transport layer (HTL) having asingle layer structure. When the first intermediate layer 221 is formedfrom a low molecular material, the first intermediate layer 221 mayinclude a hole injection layer (HIL) and a HTL.

Subsequently, as illustrated in FIG. 16, a second intermediate layer 222is formed to cover the first intermediate layer 221 and the EML 223.Obviously, the second intermediate layer 222 is not necessarily formed,and for example, when the first intermediate layer 221 and the EML 223are formed from a polymer material, the second intermediate layer 222may not be formed. When the first intermediate layer 221 and the EML 223are formed from a low molecular material, the second intermediate layer222 may be formed so that an organic light emitting device has superiorcharacteristics. In this case, the second intermediate layer 222 mayhave a single layer structure or a multi-layered structure. The secondintermediate layer 222 may include an electron transport layer (ETL)and/or an electron injection layer (EIL).

Subsequently, as illustrated in FIG. 17, at least a part of the buselectrode AL is exposed. This may be performed by forming a buselectrode hole ALH of the planarization layer 170 and a first opening221′ of the first intermediate layer 221 by removing a portion of theplanarization layer 170 on the bus electrode AL and a portion of thefirst intermediate layer 221 on the bus electrode AL. Obviously, if thesecond intermediate layer 222 exists, as illustrated in FIG. 17, asecond opening 222′ of the second intermediate layer 222 is also formed.Exposing at least a part of the bus electrode AL in this way may beperformed by irradiating a laser beam onto the first intermediate layer221 or the second intermediate layer 222. That is, the bus electrodehole ALH, the first opening 221′, and the second opening 222′ may besimultaneously formed through laser beam irradiation.

Subsequently, as illustrated in FIG. 18, an opposite electrode 230 isformed to correspond to the pixel electrode 210 and the bus electrode ALto contract the bus electrode AL through the bus electrode hole ALH, thefirst opening 221′, and the second opening 222′. The opposite electrode230 may be formed as an integral part in a plurality of pixels and maycover a display region (active region).

When the first opening 221′ and/or the second opening 222′ are formed,only a part of the bus electrode AL may be exposed, as illustrated inFIG. 17. For example, a plurality of first openings 221′ and/or secondopenings 222′ having approximately circular shapes illustrated in FIG.17 are formed in a display region of the organic light emitting displayapparatus so that the opposite electrode 230 may contact a plurality ofthe bus electrodes AL.

FIGS. 19 through 21 are cross-sectional views schematically illustratingprocesses of a method of manufacturing an organic light emitting displayapparatus.

In the method of manufacturing an organic light emitting displayapparatus according to the current embodiment of the present disclosure,as described above with reference to FIG. 16, a second intermediatelayer 222 is formed, and an auxiliary opposite electrode 231corresponding to a pixel electrode 210 and a bus electrode AL is formed,as illustrated in FIG. 19. That is, the auxiliary opposite electrode 231is formed to cover the second intermediate layer 222. If the secondintermediate layer 222 is not formed, the auxiliary opposite electrode231 may be formed to cover a first intermediate layer 221 and an EML223. A material for forming the auxiliary opposite electrode 231 may beone of the above-described materials used for forming an oppositeelectrode 230, for example.

Subsequently, as illustrated in FIG. 20, a bus electrode hole ALH of aplanarization layer 170, a first opening 221′ of the first intermediatelayer 221, a second opening 222′ of the second intermediate layer 222,and a third opening 231′ of the auxiliary opposite electrode 231 aresimultaneously formed by irradiating a laser beam onto the auxiliaryopposite electrode 231. Obviously, if the second intermediate layer 222is not formed, the bus electrode hole ALH, the first opening 221′, andthe third opening 231′ are simultaneously formed by irradiating a laserbeam onto the auxiliary opposite electrode 231.

Subsequently, as illustrated in FIG. 21, the opposite electrode 230 isformed to correspond to the pixel electrode 210 and the bus electrode ALto contact a bus electrode 210 a through the bus electrode hole ALH, thefirst opening 221′, the second opening 222′, and the third opening 231′.Obviously, even in this case, the opposite electrode 230 may be formedas an integral part in a plurality of pixels and may cover a displayregion (active region).

In the method of manufacturing an organic light emitting displayapparatus, a part of the auxiliary opposite electrode 231 is removed byirradiating a laser beam onto the auxiliary opposite electrode 231.Thus, the auxiliary opposite electrode 231 may be formed with a smallthickness so that the part of the auxiliary opposite electrode 231 maybe easily removed. If light generated in the EML 223 is irradiated tothe outside through a substrate 100, the opposite electrode 230 may beformed with a sufficient large thickness in consideration of electricalconductivity. As a result, the opposite electrode 230 may be formedthicker than the auxiliary opposite electrode 231.

When the auxiliary opposite electrode 231 and the opposite electrode 230are formed from the same material, a boundary between the auxiliaryopposite electrode 231 and the opposite electrode 230 may not occur in afinal product according to a process condition. In this case, theauxiliary opposite electrode 231 and the opposite electrode 230 may bereferred to the opposite electrode 230. As illustrated in FIG. 22, athickness t1 of another portion of the opposite electrode 230, forexample, the thickness t1 of a portion of the pixel electrode 210 islarger than the thickness t2 of a portion of the opposite electrode 230where the opposite electrode 230 contacts the bus electrode AL. This isbecause, in the portion of the pixel electrode 210, the oppositeelectrode 230 is formed twice and in the portion of the bus electrodeAL, the opposite electrode 230 is formed once.

FIGS. 23 through 26 are cross-sectional views schematically illustratingprocesses of a method of manufacturing an organic light emitting displayapparatus.

In the method of manufacturing an organic light emitting displayapparatus according to the current embodiment of the present disclosure,a bus electrode AL is formed on the same layer as a source electrode anda drain electrode of a thin film transistor TFT, and a planarizationlayer 170 is formed as an insulating layer that covers the thin filmtransistor TFT and the bus electrode AL, and subsequently, asillustrated in FIG. 23, a bus electrode hole ALH is formed to expose atleast a part of the bus electrode AL by removing at least a part of theplanarization layer 170 corresponding to the bus electrode AL. In thiscase, forming the bus electrode hole ALH may be performed simultaneouslywith forming a contact hole in the planarization layer 170 for exposinga portion to be electrically coupled with a pixel electrode 210 betweenthe source electrode and the drain electrode of the thin film transistorTFT.

Subsequently, the pixel electrode 210 is formed to be electricallycoupled with the thin film transistor TFT via the contact hole, and apixel defining layer 180 is formed on the planarization layer 170 sothat at least a central part of the pixel electrode 210 may be exposed.In this case, as illustrated in FIG. 23, the pixel defining layer 180may be formed so that at least a part of portions exposed through thebus electrode hole ALH of the bus electrode AL may be exposed.

Subsequently, as illustrated in FIG. 24, a first intermediate layer 221is formed on the pixel defining layer 180, the pixel electrode 210, andthe bus electrode AL, and an emission layer (EML) 223 is formed, and asecond intermediate layer 222 is formed, as needed. A first opening 221′is formed by removing a portion of the first intermediate layer 221 onthe bus electrode AL, and at least a part of the bus electrode AL isexposed, as illustrated in FIG. 25. If the second intermediate layer 222also exists, obviously, a second opening 222′ is also formed by removinga portion of the second intermediate layer 222 on the bus electrode ALso that at least a part of the bus electrode AL may be exposed. Formingthe first opening 221′ may be performed by irradiating a laser beam ontothe first intermediate layer 221, and if the second opening 222′ need tobe formed, the first opening 221′ and the second opening 222′ may besimultaneously formed by irradiating a laser beam onto the firstintermediate layer 221.

As illustrated in FIG. 26, an opposite electrode 230 is formed tocorrespond to the pixel electrode 210 and the bus electrode AL tocontact the bus electrode AL through the bus electrode hole ALH, thefirst opening 221′, and the second opening 222′. The opposite electrode230 may be formed as an integral part in a plurality of pixels and maycover a display region (active region).

FIGS. 27 through 29 are cross-sectional views schematically illustratingprocesses of a method of manufacturing an organic light emitting displayapparatus.

In the method of manufacturing an organic light emitting displayapparatus according to the current embodiment of the present disclosure,as described above with reference to FIG. 24, a second intermediatelayer 222 is formed, and an auxiliary opposite electrode 231corresponding to a pixel electrode 210 and a bus electrode AL is formed,as illustrated in FIG. 27. That is, the auxiliary opposite electrode 231is formed to cover the second intermediate layer 222. If the secondintermediate layer 222 is not formed, the auxiliary opposite electrode231 may be formed to cover a first intermediate layer 221 and an EML223. A material for forming the auxiliary opposite electrode 231 may beone of the above-described materials used for forming an oppositeelectrode 230, for example.

Subsequently, as illustrated in FIG. 28, a first opening 221′ of thefirst intermediate layer 221, a second opening 222′ of the secondintermediate layer 222, and a third opening 231′ of the auxiliaryopposite electrode 231 are simultaneously formed by irradiating a laserbeam onto the auxiliary opposite electrode 231. Obviously, if the secondintermediate layer 222 is not formed, the first opening 221′ and thethird opening 231′ are simultaneously formed by irradiating a laser beamonto the auxiliary opposite electrode 231.

Subsequently, as illustrated in FIG. 29, the opposite electrode 230 isformed to correspond to the pixel electrode 210 and the bus electrode ALto contact a bus electrode 210 a through a bus electrode hole ALH, thefirst opening 221′, the second opening 222′, and the third opening 231′.Obviously, even in this case, the opposite electrode 230 may be formedas an integral part in a plurality of pixels and may cover a displayregion (active region).

In the method of manufacturing an organic light emitting displayapparatus, a part of the auxiliary opposite electrode 231 is removed byirradiating a laser beam onto the auxiliary opposite electrode 231.Thus, the auxiliary opposite electrode 231 may be formed with a smallthickness so that the part of the auxiliary opposite electrode 231 maybe easily removed. If light generated in the EML 223 is irradiated tothe outside through a substrate 100, the opposite electrode 230 may beformed with a sufficient large thickness in consideration of electricalconductivity. As a result, the opposite electrode 230 may be formedthicker than the auxiliary opposite electrode 231.

When the auxiliary opposite electrode 231 and the opposite electrode 230are formed from the same material, a boundary between the auxiliaryopposite electrode 231 and the opposite electrode 230 may not occur in afinal product according to a process condition. In this case, theauxiliary opposite electrode 231 and the opposite electrode 230 may bereferred to the opposite electrode 230. As illustrated in FIG. 30, athickness t1 of another portion of the opposite electrode 230, forexample, the thickness t1 of a portion of the pixel electrode 210 islarger than the thickness t2 of a portion of the opposite electrode 230where the opposite electrode 230 contacts the bus electrode AL. This isbecause, in the portion of the pixel electrode 210, the oppositeelectrode 230 is formed twice and in the portion of the bus electrodeAL, the opposite electrode 230 is formed once.

FIG. 31 is cross-sectional view schematically illustrating process of amethod of manufacturing an organic light emitting display apparatus. Inthe method of manufacturing an organic light emitting display apparatusaccording to the current embodiment of the present disclosure, asillustrated in FIG. 16, the first intermediate layer 221, the EML 223and/or the second intermediate layer 222 are formed, and subsequently,as illustrated in FIG. 31, an opposite electrode 230 is formed on theentire surface of a display unit. Next, a laser beam is irradiated ontoat least a part of the opposite electrode 230 corresponding to a buselectrode AL so that layers between the opposite electrode 230 and thebus electrode AL are removed and the opposite electrode 230 and the buselectrode AL contact each other. Layers between the opposite electrode230 and the bus electrode AL are removed to generate heat in theopposite electrode 230 by the laser beam irradiated onto the oppositeelectrode 230 and to remove the layers between the opposite electrode230 and the bus electrode AL due to heat.

Obviously, if necessary, the first intermediate layer 221, the EML 223,the second intermediate layer 222, and the opposite electrode 230 areformed, as illustrated in FIG. 32, in a state in which the bus electrodehole ALH is formed, as illustrated in FIG. 24, and subsequently, a laserbeam is irradiated onto at least a part of the opposite electrode 230corresponding to the bus electrode AL so that the first intermediatelayer 221 and the second intermediate layer 222 between the oppositeelectrode 230 and the bus electrode AL may be removed and the oppositeelectrode 230 and the bus electrode AL may contact each other.

Until now, the method of manufacturing the organic light emittingdisplay apparatus has been described. However, aspects of the presentdisclosure are not limited thereto. For example, the organic lightemitting display apparatus manufactured using the method is also withinthe scope of the present disclosure.

For example, the organic light emitting display apparatus according toan embodiment of the present disclosure may have the configurationillustrated in FIG. 7.

The organic light emitting display apparatus according to the presentembodiment includes a pixel electrode 210 and a bus electrode 210 aformed on the same layer, are spaced apart and electrically insulatedfrom each other, a pixel defining layer 180 formed on the same layer sothat at least a part of the pixel electrode 210 including a central partthereof and at least a part of the bus electrode 210 a may be exposed,and an opposite electrode 230 formed corresponding to the pixelelectrode 210 and the bus electrode 210 a and contacts the bus electrode210 a.

The organic light emitting display apparatus according to the presentembodiment further includes a first intermediate layer 221 and a secondintermediate layer 222. The first intermediate layer 221 and the secondintermediate layer 222 are formed on a top surface of the pixel defininglayer 180 between the pixel electrode 210 and the bus electrode 210 aand on the pixel electrode 210 and the bus electrode 210 a. Obviously,an emission layer (EML) 223 may be interposed between the firstintermediate layer 221 and the second intermediate layer 222 tocorrespond to the pixel electrode 210. In some embodiments, in order toallow the bus electrode 210 a and the opposite electrode 230 to contacteach other, the first intermediate layer 221 and the second intermediatelayer 222 have a first opening 221′ and a second opening 222′ inportions of the bus electrode 210 a so that at least a part of the buselectrode 210 a may be exposed. Obviously, the second intermediate layer222 may not be formed depending on the occasion.

The organic light emitting display apparatus according to the presentembodiment includes the bus electrode 210 a, and the opposite electrode230 contacts the bus electrode 210 a. In operation electrical signalsare transmitted to the opposite electrode 230 via the bus electrode 210a having high electrical conductivity so that IR drop that may occur inthe opposite electrode 230 when no bus electrode 210 a is present may beprevented or minimized. Thus, an unintended brightness difference may beprevented from being generated in the plurality of pixels, or even whenthe unintended brightness difference is generated, the brightnessdifference may be minimized.

As described above, to allow the opposite electrode 230 and the buselectrode 210 a to contact each other, the first intermediate layer 221and/or the second intermediate layer 222 have the first opening 221′and/or the second opening 222′ so that at least a part of the buselectrode 210 a may be exposed. The first opening 221′ or the secondopening 222′ may be formed by forming the first intermediate layer 221and/or the second intermediate layer 222 on the entire surface of thesubstrate 100, by irradiating a laser beam onto predetermined portionsof the first intermediate layer 221 and/or the second intermediate layer222 and by removing at least a part of the portions onto which the laserbeam is irradiated so that a manufacturing yield may be improved. Thus,in the organic light emitting display apparatus according to the presentembodiment, a portion of the first intermediate layer 221 adjacent tothe first opening 221′ may be a portion that has deteriorated byexposure to a high-temperature heat. This also applies to the secondopening 222′ of the second intermediate layer 222.

FIG. 8 is a photo schematically showing a part of the organic lightemitting display apparatus illustrated in FIG. 6. In some embodiments asillustrated in FIG. 8, as the laser beam may be irradiated onto thefirst intermediate layer 221 and the second intermediate layer 222,portions of the first intermediate layer 221 and the second intermediatelayer 222 are removed so that a part of the bus electrode 210 a may beexposed. As the laser beam is directly irradiated onto the secondintermediate layer 222, as illustrated in FIG. 8, the second opening222′ of the second intermediate layer 222 onto which the laser beam isdirectly irradiated, is larger than the first opening 221′ of the firstintermediate layer 221. In FIG. 8, the first opening 221′ and the secondopening 222′ have approximately circular shapes, and a radius r2 of thesecond opening 222′ is larger than a radius r1 of the first opening221′. The first opening 221′ and the second opening 222′ aresimultaneously formed so that their centers are substantially alignedwith each other when viewed in a direction substantially normal to eachopening.

When the first opening 221′ and/or the second opening 222′ is formed,only a part of the bus electrode 210 a may be exposed, as illustrated inFIG. 8. For example, a plurality of first openings 221′ and/or secondopenings 222′ having approximately circular shapes illustrated in FIG. 8are formed in a display region of the organic light emitting displayapparatus so that the opposite electrode 230 may contact a plurality ofthe bus electrodes 210 a.

The first intermediate layer 221 and the EML 223 are very vulnerable toexternal impurities, such as moisture. Thus, if a portion of the firstintermediate layer 221 is removed by irradiating the laser beam onto thefirst intermediate layer 221 in a state where only the firstintermediate layer 221 and the EML 223 are formed without forming thesecond intermediate layer 222, the first intermediate layer 221 and theEML 223 may be damaged. Thus, the first opening 221′ and the secondopening 222′ may be simultaneously formed by irradiating the laser beamonto the opposite electrode 230 after the second intermediate layer 222has been formed. For example, when the second intermediate layer 222includes at least one of LiF and Liq, an ohmic contact of the oppositeelectrode 230 may be smoothly performed. When the second intermediatelayer 222 includes at least one of LiF and Liq, vulnerability toexternal impurities is improved, and damage of the first intermediatelayer 221, the EML 223, and the second intermediate layer 222 may beefficiently prevented when the first opening 221′ and the second opening222′ are formed by irradiating the laser beam onto the oppositeelectrode 230.

Obviously, in order to prevent damage of the first intermediate layer221, the EML 223 and/or the second intermediate layer 222, after theopposite electrode 230 has been formed, the laser beam is irradiatedonto at least a part of the opposite electrode 230 corresponding to thebus electrode 210 a, and at least a part of the first intermediate layer221 and/or the second intermediate layer 222 between the oppositeelectrode 230 and the bus electrode 210 a is removed so that theopposite electrode 230 and the bus electrode 210 a contact each other.Even in this case, the organic light emitting display apparatus may havethe structure illustrated in FIG. 7.

An organic light emitting display apparatus according to anotherembodiment of the present disclosure may have the configurationillustrated in FIG. 12. That is, the organic light emitting displayapparatus may further include an auxiliary opposite electrode 231 formedon a surface in a direction of the first intermediate layer 221 of theopposite electrode 230 to contact the opposite electrode 230 and thathas a third opening 231′ corresponding to the first opening 221′ of thefirst intermediate layer 221. That is, the auxiliary opposite electrode231 may correspond to the opposite electrode 230 in a portion of thefirst intermediate layer 221 not including the first opening 221′. Theorganic light emitting display apparatus according to the presentembodiment may prevent or minimize an IR drop of the opposite electrode230 via the bus electrode 210 a. When the first opening 221′ and/or thesecond opening 222′ is formed in the first intermediate layer 221 and/orthe second intermediate layer 222, the first intermediate layer 221, theEML 223 and/or the second intermediate layer 222, which are formed belowthe auxiliary opposite electrode 231, are protected by the auxiliaryopposite electrode 231 so that damage of the first intermediate layer221, the EML 223 and/or the second intermediate layer 222 may beefficiently prevented. The thickness of the auxiliary opposite electrode231 may be smaller than the thickness of the opposite electrode 230.

The auxiliary opposite electrode 231 and the opposite electrode 230 maybe formed as an integral part in some embodiments as illustrated in FIG.13. It will be understood that the thickness t2 of a portion of theopposite electrode 230 corresponding to the first opening 221′ of thefirst intermediate layer 221 is smaller than the thickness t1 of anotherportion of the opposite electrode 230, for example, the thickness t1 ofa portion of the pixel electrode 210.

An organic light emitting display apparatus according to anotherembodiment of the present disclosure may have the configurationillustrated in FIG. 18.

The organic light emitting display apparatus according to the currentembodiment of the present disclosure includes a bus electrode AL, aplanarization layer 170 that is an insulating layer covering the buselectrode AL and having a bus electrode hole ALH exposing at least apart of the bus electrode AL, a pixel defining layer 180 that isdisposed on the planarization layer 170 and exposes at least a part of apixel electrode 210 including a central part thereof and portionsexposed through the bus electrode hole ALH, and an opposite electrode230 that is disposed to correspond to the pixel electrode 210 and thebus electrode AL and contacts the bus electrode AL. The bus electrode ALmay be disposed on the same layer as at least one of a source electrode,a drain electrode, and a gate electrode of a thin film transistor TFT.In FIG. 18, the source electrode and the drain electrode are locatedabove the gate electrode, and the bus electrode AL is disposed on thesame layer as the source electrode and the drain electrode.

Furthermore, the organic light emitting display apparatus according tothe current embodiment of the present disclosure includes a firstintermediate layer 221 and a second intermediate layer 222. The firstintermediate layer 221 and the second intermediate layer 222 aredisposed on the pixel defining layer 180 and the pixel electrode 210.Obviously, the first intermediate layer 221 and the second intermediatelayer 222 may also be disposed on the planarization layer that is aninsulating layer in the vicinity of the bus electrode hole ALH, asillustrated in FIG. 18. An emission layer (EML) 223 may be interposedbetween the first intermediate layer 221 and the second intermediatelayer 222 to correspond to the pixel electrode 210. In this case, toallow the bus electrode AL and the opposite electrode 230 to contacteach other, the first intermediate layer 221 and the second intermediatelayer 222 have a first opening 221′ and a second opening 222′ inportions of the first intermediate layer 221 and the second intermediatelayer 222 on the bus electrode AL so that at least a part of the buselectrode AL may be exposed. Obviously, the second intermediate layer222 may not exist, as occasion demands.

In the organic light emitting display apparatus according to the currentembodiment of the present disclosure, the bus electrode AL is formed,and the opposite electrode 230 contacts the bus electrode AL, andelectrical signals are transmitted to the opposite electrode 230 via thebus electrode AL having high electrical conductivity. Thus, an IR dropthat may occur when no bus electrode AL is present may be prevented orminimized. Thus, an unintended brightness difference may be preventedfrom being generated in a plurality of pixels, or even when theunintended brightness difference is generated, the brightness differencemay be minimized.

As described above, to allow the opposite electrode 230 and the buselectrode AL to contact each other, the first intermediate layer 221and/or the second intermediate layer 222 have the first opening 221′and/or the second opening 222′ in portions of the first intermediatelayer 221 and/or the second intermediate layer 222 on the bus electrodeAL so that at least a part of the bus electrode AL may be exposed. Thefirst opening 221′ or the second opening 222′ may be formed by formingthe first intermediate layer 221 and/or the second intermediate layer222 on the entire surface of the substrate 100, by irradiating a laserbeam onto predetermined portions of the first intermediate layer 221and/or the second intermediate layer 222 and by removing at least a partof the portions onto which the laser beam is irradiated so that amanufacturing yield may be improved. Thus, in the organic light emittingdisplay apparatus according to the present embodiment, a portion of thefirst intermediate layer 221 adjacent to the first opening 221′ may be aportion that has deteriorated by exposure to a high-temperature heat.This also applies to the second opening 222′ of the second intermediatelayer 222.

When the first opening 221′ and the second opening 222′ are formed byirradiating a laser beam onto the first intermediate layer 221 and thesecond intermediate layer 222, as the laser beam is directly irradiatedonto the second intermediate layer 222, the second opening 222′ of thesecond intermediate layer 222 onto which the laser beam is directlyirradiated, is larger than the first opening 221′ of the firstintermediate layer 221. In this case, the first opening 221′ and thesecond opening 222′ are simultaneously formed so that their centers aresubstantially aligned with each other when viewed in a directionsubstantially normal to each opening.

When the first opening 221′ and/or the second opening 222′ are formed,only a part of the bus electrode AL may be exposed, as illustrated inFIG. 18. For example, a plurality of first openings 221′ and/or secondopenings 222′ having approximately circular shapes are formed in adisplay region of the organic light emitting display apparatus so thatthe opposite electrode 230 may contact a plurality of the bus electrodesAL.

The first intermediate layer 221 and the EML 223 are very vulnerable toexternal impurities from the outside, such as moisture. Thus, if aportion of the first intermediate layer 221 is removed by irradiatingthe laser beam onto the first intermediate layer 221 in a state whereonly the first intermediate layer 221 and the EML 223 are formed withoutforming the second intermediate layer 222, the first intermediate layer221 and the EML 223 may be damaged. Thus, the first opening 221′ and thesecond opening 222′ may be simultaneously formed by irradiating thelaser beam onto the opposite electrode 230 after the second intermediatelayer 222 has been formed. For example, when the second intermediatelayer 222 includes at least one of LiF and Liq, an ohmic contact of theopposite electrode 230 may be smoothly performed. When the secondintermediate layer 222 includes at least one of LiF and Liq,vulnerability to external impurities is improved, and damage of thefirst intermediate layer 221, the EML 223, and the second intermediatelayer 222 may be efficiently prevented when the first opening 221′ andthe second opening 222′ are formed by irradiating the laser beam ontothe opposite electrode 230.

Obviously, in order to prevent damage of the first intermediate layer221, the EML 223 and/or the second intermediate layer 222, after theopposite electrode 230 has been formed, the laser beam is irradiatedonto at least a part of the opposite electrode 230 corresponding to thebus electrode AL, and at least a part of the first intermediate layer221 and/or the second intermediate layer 222 between the oppositeelectrode 230 and the bus electrode AL is removed so that the oppositeelectrode 230 and the bus electrode AL contact each other. Even in thiscase, the organic light emitting display apparatus may have thestructure illustrated in FIG. 18.

As described above, to allow the opposite electrode 230 and the buselectrode AL to contact each other, the first intermediate layer 221and/or the second intermediate layer 222 have the first opening 221′and/or the second opening 222′ in portions of the first intermediatelayer 221 and/or the second intermediate layer 222 on the bus electrodeAL so that at least a part of the bus electrode AL may be exposed. Thefirst opening 221′ or the second opening 222′ may be formed by formingthe first intermediate layer 221 and/or the second intermediate layer222 on the entire surface of the substrate 100, by irradiating a laserbeam onto predetermined portions of the first intermediate layer 221and/or the second intermediate layer 222 and by removing at least a partof the portions onto which the laser beam is irradiated so that amanufacturing yield may be improved. Thus, in the organic light emittingdisplay apparatus according to the present embodiment, a portion of thefirst intermediate layer 221 adjacent to the first opening 221′ may be aportion that has deteriorated by exposure to a high-temperature heat.This also applies to the second opening 222′ of the second intermediatelayer 222.

An organic light emitting display apparatus according to anotherembodiment of the present disclosure may have the configurationillustrated in FIG. 21. That is, the organic light emitting displayapparatus may further include an auxiliary opposite electrode 231 formedon a surface in a direction of the first intermediate layer 221 of theopposite electrode 230 to contact the opposite electrode 230 and thathas a third opening 231′ corresponding to the first opening 221′ of thefirst intermediate layer 221. That is, the auxiliary opposite electrode231 may correspond to the opposite electrode 230 in a portion of thefirst intermediate layer 221 not including the first opening 221′.

The organic light emitting display apparatus according to the presentembodiment may prevent or minimize an IR drop of the opposite electrode230 via the bus electrode AL. When the first opening 221′ and/or thesecond opening 222′ is formed in the first intermediate layer 221 and/orthe second intermediate layer 222, the first intermediate layer 221, theEML 223 and/or the second intermediate layer 222, which are formed belowthe auxiliary opposite electrode 231, are protected by the auxiliaryopposite electrode 231 so that damage of the first intermediate layer221, the EML 223 and/or the second intermediate layer 222 may beefficiently prevented. The thickness of the auxiliary opposite electrode231 may be smaller than the thickness of the opposite electrode 230.

The auxiliary opposite electrode 231 and the opposite electrode 230 maybe formed as an integral part, as illustrated in FIG. 22. In this case,it will be understood that the thickness t2 of a portion of the oppositeelectrode 230 corresponding to the first opening 221′ of the firstintermediate layer 221 is smaller than the thickness t1 of anotherportion of the opposite electrode 230, for example, the thickness t1 ofa portion of the pixel electrode 210.

As described above, according to the one or more embodiments of thepresent disclosure, an organic light emitting display apparatus that canbe easily manufactured and has high luminous stability and a method ofmanufacturing the same are provided. Obviously, the scope of the presentdisclosure is not limited by the effects.

While the present invention has been particularly shown and describedwith reference to exemplary embodiments thereof, it will be appreciatedby those skilled in the art that various modifications and changes maybe made without departing from the scope of the present disclosure. Itwill also be appreciated by those of skill in the art that partsincluded in one embodiment are interchangeable with other embodiments;one or more parts from a depicted embodiment can be included with otherdepicted embodiments in any combination. For example, any of the variouscomponents described herein and/or depicted in the Figures may becombined, interchanged or excluded from other embodiments. With respectto the use of substantially any plural and/or singular terms herein,those having skill in the art can translate from the plural to thesingular and/or from the singular to the plural as is appropriate to thecontext and/or application. The various singular/plural permutations maybe expressly set forth herein for sake of clarity. Thus, while thepresent disclosure has described certain exemplary embodiments, it willbe understood by those of ordinary skill in the art that various changesin form and details may be made therein without departing from thespirit and scope of the present invention as defined by the followingclaims.

What is claimed is:
 1. An organic light emitting display apparatuscomprising: a bus electrode; an insulating layer covering the buselectrode and having a bus electrode hole so that at least a part of thebus electrode is exposed through the bus electrode hole; a pixelelectrode formed on the insulating layer and electrically coupled withthe bus electrode; a pixel defining layer formed on the insulating layerso that at least a part of the pixel electrode including a central partthereof and at least the part of the bus electrode exposed through thebus electrode hole are exposed; a first intermediate layer formed on thepixel defining layer and the pixel electrode, the first intermediatehaving a first opening corresponding to the bus electrode hole of theinsulating layer so that at least the part of the bus electrode isexposed; an emission layer formed on the first intermediate layercorresponding to the pixel electrode; and an opposite electrode formedon the emission layer corresponding to the pixel electrode and the buselectrode, the opposite electrode contacting the bus electrode throughthe first opening of the first intermediate layer and the bus electrodehole of the insulating layer.
 2. The organic light emitting displayapparatus of claim 1, further comprising a thin film transistorincluding a source electrode, a drain electrode, and a gate electrode,wherein the bus electrode is on a same layer as at least one of thesource electrode, the drain electrode, and the gate electrode.
 3. Theorganic light emitting display apparatus of claim 2, wherein the sourceelectrode and the drain electrode are located above the gate electrode,and the bus electrode is on a same layer as the source electrode and thedrain electrode.
 4. The organic light emitting display apparatus ofclaim 1, wherein the first opening of the first intermediate layerexposes only a part of the bus electrode.
 5. The organic light emittingdisplay apparatus of claim 1, wherein a portion of the firstintermediate layer adjacent to the first opening is a portion that hasdeteriorated from exposure to heat.
 6. The organic light emittingdisplay apparatus of claim 1, further comprising an auxiliary oppositeelectrode formed on a surface toward the first intermediate layer of theopposite electrode to contact the opposite electrode, the auxiliaryopposite electrode having a third opening corresponding to the firstopening of the first intermediate layer.
 7. The organic light emittingdisplay apparatus of claim 6, wherein a thickness of the auxiliaryopposite electrode is smaller than the thickness of the oppositeelectrode.
 8. The organic light emitting display apparatus of claim 6,wherein the auxiliary opposite electrode corresponds to the oppositeelectrode in a portion of the first intermediate layer not including thefirst opening.
 9. The organic light emitting display apparatus of claim1, wherein a thickness of a portion of the opposite electrodecorresponding to the first opening of the first intermediate layer issmaller than the thickness of another portion of the opposite electrode.10. The organic light emitting display apparatus of claim 1, furthercomprising a second intermediate layer formed between the firstintermediate layer and the opposite electrode to cover the firstintermediate layer and the emission layer, the second intermediate layerhaving a second opening corresponding to the first opening of the firstintermediate layer so that the opposite electrode contacts the buselectrode through the first opening and the second opening.
 11. Theorganic light emitting display apparatus of claim 10, wherein the secondopening is larger than the first opening.
 12. The organic light emittingdisplay apparatus of claim 11, wherein a center of the second openingand a center of the first opening are substantially aligned with eachother when viewed from a direction normal to both the first opening andthe second opening.
 13. The organic light emitting display apparatus ofclaim 10, wherein a portion of the second intermediate layer adjacent tothe second opening is a portion deteriorated from heat exposure.
 14. Theorganic light emitting display apparatus of claim 10, wherein the secondintermediate layer is formed from at least one of LiF and Liq.
 15. Amethod of manufacturing an organic light emitting display apparatus, themethod comprising: forming a bus electrode; forming an insulating layercovering the bus electrode; forming a pixel electrode on the insulatinglayer; forming a pixel defining layer on the insulating layer so atleast a part of the pixel electrode including a central part thereof isexposed; forming a first intermediate layer on the pixel defining layerand the pixel electrode; forming an emission layer on the firstintermediate layer corresponding to the pixel electrode; exposing atleast a part of the bus electrode; and forming an opposite electrodecorresponding to the pixel electrode and the bus electrode to contactthe bus electrode.
 16. The method of claim 15, wherein the forming ofthe bus electrode comprises forming the bus electrode on a same layer asat least one of a source electrode, a drain electrode, and a gateelectrode of a thin film transistor.
 17. The method of claim 15, furthercomprising forming a bus electrode hole exposing at least the part ofthe bus electrode by removing at least a portion of the insulating layercorresponding to the bus electrode, wherein the forming of the pixeldefining layer comprises forming the pixel defining layer on theinsulating layer so that at least the part of the bus electrode exposedthrough the bus electrode hole is exposed; wherein the forming of thefirst intermediate layer comprises forming the first intermediate layeron the pixel defining layer, the pixel electrode, and the bus electrode;and wherein the exposing at least the part of the bus electrodecomprises forming a first opening by removing a portion of the firstintermediate layer on the bus electrode.
 18. The method of claim 17,wherein the forming of the first opening comprises forming the firstopening through which only a part of the bus electrode is exposed. 19.The method of claim 17, wherein the forming of the first openingincludes irradiating a laser beam onto the first intermediate layer. 20.The method of claim 17, further comprising, after the forming of theemission layer and before the forming of the first opening, forming anauxiliary opposite electrode corresponding to the pixel electrode andthe bus electrode, wherein the first opening in the first intermediatelayer is formed along with a third opening in the auxiliary oppositeelectrode by removing a portion of the first intermediate layer on thebus electrode and a portion of the auxiliary opposite electrode on thebus electrode to expose at least a part of the bus electrode; andwherein the opposite electrode is formed to correspond to the pixelelectrode and the bus electrode to contact the bus electrode through thefirst opening in the first intermediate layer and the third opening inthe auxiliary opposite electrode.
 21. The method of claim 20, whereinthe first opening in the first intermediate layer and the third openingin the auxiliary opposite electrode are simultaneously formed byirradiating a laser beam onto the auxiliary opposite electrode.
 22. Themethod of claim 20, wherein the opposite electrode is formed to bethicker than the auxiliary opposite electrode.
 23. The method of claim17, further comprising, after the forming of the emission layer andbefore the forming of the first opening, forming a second intermediatelayer to cover the first intermediate layer and the emission layer,wherein the first opening in the first intermediate layer is formedalong with a second opening in the second intermediate layer by removinga portion of the first intermediate layer on the bus electrode and aportion of the second intermediate layer on the bus electrode so that atleast a part of the bus electrode is exposed; and wherein the oppositeelectrode is formed to correspond to the pixel electrode and the buselectrode to contact the bus electrode through the first opening of thefirst intermediate layer and the second opening of the secondintermediate layer.
 24. The method of claim 23, wherein the firstopening in the first intermediate layer and the second opening in thesecond intermediate layer are simultaneously formed by irradiating alaser beam onto the second intermediate layer.
 25. The method of claim15, wherein the forming of the pixel defining layer comprises formingthe pixel defining layer on the insulating layer so that at least thepart of the pixel electrode including the central part thereof and atleast a part of the insulating layer corresponding to the bus electrodeare exposed, and wherein the exposing at least the part of the buselectrode comprises forming a bus electrode hole of the insulating layerand a first opening of the first intermediate layer by removing aportion of the insulating layer on the bus electrode and a portion ofthe first intermediate layer on the bus electrode so that at least thepart of the bus electrode is exposed.
 26. The method of claim 25,wherein the forming of the bus electrode hole and the first openingcomprises irradiating a laser beam onto the first intermediate layer.27. The method of claim 25, further comprising after the forming of theemission layer and before the forming of the bus electrode hole and thefirst opening, forming an auxiliary opposite electrode corresponding tothe pixel electrode and the bus electrode, wherein the forming of thebus electrode hole and the first opening comprises forming a buselectrode hole of the insulating layer, a first opening of the firstintermediate layer, and a third opening of the auxiliary oppositeelectrode by removing a portion of the insulating layer on the buselectrode, a portion of the first intermediate layer on the buselectrode, and a portion of the auxiliary opposite electrode on the buselectrode so that at least the part of the bus electrode is exposed; andwherein the forming of the opposite electrode comprises forming theopposite electrode to correspond to the pixel electrode and the buselectrode to contact the bus electrode through the bus electrode hole inthe insulating layer, the first opening in the first intermediate layer,and the third opening in the auxiliary opposite electrode.
 28. Themethod of claim 27, wherein the forming of the bus electrode hole, thefirst opening, and the third opening comprises irradiating a laser beamonto the auxiliary opposite electrode so that the bus electrode hole,the first opening, and the third opening are simultaneously formed. 29.The method of claim 27, wherein the opposite electrode is formed to bethicker than the auxiliary opposite electrode.
 30. The method of claim25, further comprising, after the forming of the emission layer andbefore the forming of the first opening, forming a second intermediatelayer to cover the first intermediate layer and the emission layer,wherein the forming of the bus electrode hole and the first openingcomprises forming a bus electrode hole of the insulating layer, a firstopening of the first intermediate layer, and a second opening of thesecond intermediate layer by removing a portion of the insulating layeron the bus electrode, a portion of the first intermediate layer on thebus electrode, and a portion of the second intermediate layer on the buselectrode so that at least the part of the bus electrode is exposed; andwherein the forming of the opposite electrode comprises forming theopposite electrode to correspond to the pixel electrode and the buselectrode to contact the bus electrode through the bus electrode hole inthe insulating layer, the first opening in the first intermediate layer,and the second opening in the second intermediate layer.
 31. The methodof claim 30, wherein the forming of the bus electrode hole, the firstopening, and the second opening comprises irradiating a laser beam ontothe second intermediate layer so that the bus electrode hole, the firstopening, and the second opening are simultaneously formed.
 32. A methodof manufacturing an organic light emitting display apparatus, the methodcomprising: forming a bus electrode; forming an insulating layercovering the bus electrode; forming a pixel electrode on the insulatinglayer; forming a pixel defining layer on the insulating layer so that atleast a part of the pixel electrode including a central part thereof isexposed; forming a first intermediate layer on the pixel defining layerand the pixel electrode; forming an emission layer on the firstintermediate layer corresponding to the pixel electrode; forming anopposite electrode to correspond to the pixel electrode and the buselectrode; and irradiating a laser beam onto at least a part of theopposite electrode corresponding to the bus electrode so that at least apart of layers between the opposite electrode and the bus electrode isremoved and the opposite electrode and the bus electrode contact eachother.